Abstract

As social interest in health increases, interest in oral health and preservation of natural teeth are also increas ing. The hard tissues in the oral cavity undergo physical changes as age increases. One of the changes is the progress of tooth cracks in natural or restored teeth. These cracks are commonly encountered in daily clinical practice but often confuse the operator due to its difficulties in diagnosis and therapeutic access. Diagnosing a cracked tooth has been a chanllenge to dental clinicians. For the diagnosis of a cracked tooth, the quantitative light-induced fluorescent (QLF) device, which is capable of detecting fluorescent reactions of the tooth with visible light (405nm), has been introduced as one of the methods for observing tooth cracks. Specific metabolites of microorganisms that penetrate through the crack’s line react with specific autofluorescence to 405nm visible light emitted from the QLF device. These fluorescent image provided by the QLF helps to observe the location of the crack during the diagnosis of a cracked tooth and helps the patient’s dental record. The QLF images provided a magnified image as well as a fluorescent im age that could identify the location of the crack existing outside the tooth, around the restoration, and inside the cavity after removal of the restoration by a simple process of capturing images. This report shows the process of diagnosis of a cracked tooth using a QLF device by observing three separate cases which can help clinicians to understand this process.